[ Adding Dan Williams and dri-devel ] On 14/10/16 03:28 AM, Shawn Starr wrote: > Hello AMD folks, > > I have discovered a problem in Linus master that affects AMDGPU, nobody would > notice this in drm-next-4.9-wip since its not in this repo. [...] > 87744ab3832b83ba71b931f86f9cfdb000d07da5 is the first bad commit > commit 87744ab3832b83ba71b931f86f9cfdb000d07da5 > Author: Dan Williams <dan.j.williams at intel.com> > Date: Fri Oct 7 17:00:18 2016 -0700 > > mm: fix cache mode tracking in vm_insert_mixed() > > vm_insert_mixed() unlike vm_insert_pfn_prot() and vmf_insert_pfn_pmd(), > fails to check the pgprot_t it uses for the mapping against the one > recorded in the memtype tracking tree. Add the missing call to > track_pfn_insert() to preclude cases where incompatible aliased mappings > are established for a given physical address range. > > Link: http://lkml.kernel.org/r/ > 147328717909.35069.14256589123570653697.stgit at dwillia2- > desk3.amr.corp.intel.com > Signed-off-by: Dan Williams <dan.j.williams at intel.com> > Cc: David Airlie <airlied at linux.ie> > Cc: Matthew Wilcox <mawilcox at microsoft.com> > Cc: Ross Zwisler <ross.zwisler at linux.intel.com> > Signed-off-by: Andrew Morton <akpm at linux-foundation.org> > Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org> > > :040000 040000 7517c0019fe49c1830b5a1d81f1dc099c5aab98a > fd497a604a2af5995db2b8ed1e9c640bede6adf3 M mm > > > Removal of this patch stops graphics stalls. Thanks for bisecting this Shawn. > A friend of mine mentions, > > "looks like a graphics thingy you depend on is requesting a mapping with a > not-allowed cache mode, and now you are (rightfully) getting errors?" It would be nice to get some more specific pointers what amdgpu (or maybe ttm, since that calls vm_insert_mixed in ttm_bo_vm_fault) might be doing wrong. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer
